WEBVTT
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to figure out if this is a 1 to 1
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function. Let's just make a rough sketch of what's
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going on. So we have time and we have
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the height of the football on. What's going to
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happen is the football is probably going up first and
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then it's on its way back down. So is
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that a 1 to 1 function? Well, To
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be a 1 to 1 function, it must pass
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the vertical line test for every X value. There's
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only one Y value and the horizontal line test for
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every Y value. There's only one X value,
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so it passes the vertical line test. That's what
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makes it a function in the first place, but
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it fails a horizontal line test because there are places
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where it passes through multiple points on a horizontal line
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. So that was a fail. So, no
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, this is not a 1 to 1 function